アルゼンチンで生産されたCamellia Sinensis由来の茶葉のフッ化物濃度

Fluoride concentration in teas derived from Camellia Sinensis produced in Argentina.

抄録

アルゼンチンで生産・商品化されているCamellia sinensis由来の茶葉のフッ化物濃度およびpHを評価すること。紅茶（n=16），緑茶（n=21），赤茶（n=7），白茶（n=4）の48品種の茶葉またはティーバッグを入手した．各製品1袋または2.0±0.05gを200mLの蒸留沸騰水で5分間煎じた。イオン選択性電極を用いてフッ化物濃度を，pHメータを用いてpHを測定した．フッ素濃度は0.1〜9.7μg/mL，pHは2.7〜5.1であった．茶葉群では，ティーバッグ群（1.10±0.82µg/mL）よりも高いフッ化物濃度が認められた（p<0.05）．お茶の種類については、緑茶と紅茶は紅茶と白茶よりもFが豊富であった。フッ化物とpHは相関がないように見えた（ピアソン検定）。すべての茶試料は，飲料水として推奨される閾値を超えるフッ化物濃度を示した．pH は低く，歯の侵食摩耗の危険性があることが判明した．

To evaluate the fluoride concentration and pH of tea derived from Camellia sinensis produced and commercialized in Argentina. Forty-eight varieties of tea (black (n = 16), green (n = 21), red (n = 7), and white (n = 4)) commercialized in the form of leaves or tea bags were acquired. One bag or 2.0 ± 0.05 g of each product was infused for 5 min in 200 mL of distilled boiled water. The F concentration was determined using an ion-selective electrode and pH was measured using a pH meter. The found fluoride concentrations ranged from 0.1 to 9.7 µg/mL and the pH ranged from 2.7 to 5.1. A higher fluoride concentration was observed in the leaves group (2.75 ± 2.65 µg/mL) compared to tea bags (1.10 ± 0.82 µg/mL) (p < 0.05). Regarding the type of tea, green and black tea were richer in F than red and white tea. Fluoride and pH appeared not to be correlated (Pearson test). All the studied tea samples presented fluoride concentrations greater than the threshold recommended for drinking water. The pH proved to be low, which could be a risk for erosive tooth wear.